Query users in Exchange and make sure user is within an array

I am not getting the right return from the array. I am not getting a match, even if the user is in the array:

$MailboxArray = Get-Mailbox | Select Alias,IsMailboxEnabled

$UserAlias = @()
ForEach ($MailboxAlias in $MailboxArray)
{
$Alias = $MailboxAlias.Alias
$Status = $MailboxAlias.IsMailboxEnabled
$AliasList = New-Object -TypeName PSObject -Property @{
Name = $Alias
Status = $Status }

$UserAlias += $AliasList

}

$UserAliasInfo = $UserAlias | Select Name,Status

$Username = "mng"

If (($Username -match $UserAlias) -and ($Status -eq "Enabled"))
{
Write-Host "Match"
}